Audi S4 (B5)

2000 Audi S4
2001 Audi S4
2001.5 Audi S4
2002 Audi S4

b5s4 01This second generation Audi S4 was available in Europe in 1997-2002 alongside the 'face-lifted' A4 sedan release. In 1998 a wagon version title the Avant became available. North America waited until 2000 before the S4's were available.

Production of this car shows the following numbers: 14734 Sedans, 1539 Avants from 1997-2002.

b5s4 02b5s4 avant



250 HP @ 5,800 rpm
258 ft lb @ 1,850 rpm

Curb Weight:
1,680 kg / 3696 lbs

Dual turbo compressors
2671cc (2.7 litre) V6 engine
81 mm bore, 86.4 mm stroke
30 valves (5 per cylender)
9:3:1 compression ratio
double overhead cam
variable valve timing/camshaft

apb cutaway

Premium unleaded fuel
Fuel economy EPA highway (l/100km): 9.8
Multi-point injection fuel system
Main 62 litre fuel tank

Quattro AWD system
Four disc brakes including four ventilated discs
Fullsize alloy rim internal spare wheel
Multi-link front suspension with stabilizer bar independent with coil springs
wishbone rear suspension with stabilizer bar independent with coil springs

Body side molding
Front and rear body color bumpers
Chrome/bright trim around side windows
Coefficient of drag: 0.31
Driver and passenger power heated body color door mirrors

External Dimensions:
overall length (mm): 4,483
overall width (mm): 1,849
overall height (mm): 1,417
wheelbase (mm): 2,606
front track (mm): 1,496
rear track (mm): 1,491 and curb to curb turning circle (mm): 11,400

Front fog lights (Canadian models did not receive fog lights)
Projector beam lens Xenon bulb headlights (Canadian models did not receive Xenon lights, halogen H7 bulbs instead)
Luxury trim leather on gearknob
Metallic paint , black paint , gloss paint , mica paint
Rear window
Tinted glass on cabin, rear and side

Windshield wipers with automatic intermittent wipe

Air conditioning with climate control
Diversity antenna
Anti-theft protection
Front and rear ashtray
Audio anti-theft protection:
Manufacturer's own audio system
Cargo capacity: all seats in place - 388 litres
Front seats cigar lighter
Digital Clock
Computer with average speed, average fuel consumption, instantaneous fuel consumption and range for remaining fuel
Dashboard full console with open storage box, floor full console with covered storage box
Delayed/fade courtesy lights
Cruise control
Front seats cup holders
Door ajar warning
Door pockets/bins for driver seat and passenger seat
External temperature
Driver and passenger front airbag
Bucket seat
3-point reel height adjustable front seat belts on driver seat and passenger seat with pre-tensioners
Front seat center armrest
Lockable glove compartment
Height adjustable two head restraints on front seats and rear seats
Headlight control
Illuminated entry system
Internal dimensions: front headroom (mm): 968, rear headroom (mm): 935, front leg room (mm): 1,049, rear leg room (mm): 848, front shoulder room (mm): 1,389, rear shoulder room (mm): 1,356 and interior volume (liters): 2,483
Low fuel level warning
Remote power locks includes trunk/hatch and includes power windows
Vehicle speed proportional power steering
Front and rear power windows with two one-touch
Front and rear reading lights
3-point reel rear seat belts on driver side with pre-tensioners , 3-point reel rear seat belts on passenger side with pre-tensioners , lap reel rear seat belts on center side
Rear seat center armrest
Split bench asymmetrical three rear seats
Rear view mirror
Front seat back storage
Leather seat upholstery
Seating: five seats
Service interval indicator
Front side airbag
Eight speakers
Leather covered steering wheel
Driver and passenger illuminated vanity mirror
Ventilation system with recirculation setting and micro filter


This car raised a lot of eye brows upon its release and still resonates heavily within car enthusiast communities. B5S4's stock a 2.7L bi-turbo motor shoehorned under the hood with a low compression ratio of 9:3:1 outputting 250 HP. You should be quick to realize this to be a very modest factory tune. And the tuning companies did exactly that, soon after the release, multiple companies began selling ECU software upgrades offering massive power gains. Boost hungry individuals often replace the factory Borg Warner K03 turbos with larger K04 units from the RS4 or other Audi models. Of course drivetrain, fueling, exhaust flow and other areas are factored into turbo upgrades. There are number of full kits available which offer power output in the 450 HP/450 TQ range.
11 years after its initial release, tuning companies continue to develop new products for the B5S4.
Often modifying an area of a car necessitates the upgrading of other areas. Like many other cars, systematic upgrading of these cars has been unofficially categorized into the following Stages:

Stage 1 (increase of ~ 50-60HP @ flywheel) - Chip
Originally tuning companies would receive the ECU from the cars owner and then solder a chip onto the ECU's wafer. This chip contains the modified air fuel mappings and timing specs which the ECU will operate with (bypassing the original code). Currently, all of the chip manufactures are now able to 'flash' the memory tables of the ECU with their modified code. This method is much less time consuming and less intrusive. Multiple tuning companies offer solutions which allow the cars owner to switch between different modes. Which is nice if you want to revert back to original running specs.

Stage 2 (increase of ~ 5-15 HP@ flywheel) - Exhaust System
Catalytic converter - back exhaust system teamed with a chip gets you to Stage 2.

Stage 2.5 (increase of ~ 20-35HP @ flywheel) - Downpipes and High Flow Cat
Replace the original downpipes which span from turbos to catalytic converter and replace catalytic converter with a high flow variant.

Stage 3 ( ~450-450 total HP @ flywheel) - Turbo Upgrade
Typically replace K03 turbo chargers with Borg Warner K04 turbos, such as those used in the european RS4 wagon. Other turbo kits are available which utilize Garrett and Tial turbo chargers. This stage usually requires more than just the turbos be upgraded. Often fueling, air intake and drivetrain upgrades will need to be applied.

Other common modifications are:
  • Adjustable Suspension
  • Drivetrain Stabalizer Bar
  • Larger Sway bars
  • Boost Guage
  • Methenol/water injection

Common Problems

K03 Turbo failure:
Pay attention to this one, the total cost of replacement is very high. These units have a reputation for failing prematurely. It's hard to determine if user abuse is the main contributor to the breakdown of the turbos. Proper oil warm up before and adequate oil cool down after hard usage will certainly increase the life of these units and should be considered part of the ritual when enjoying your B5S4.

Throttle Body Boot Tearing:
Located at the top of the top/middle of the motor close to the front of the car, there is a rubber boot which directs the charged intake through to the throttle body. This OEM rubber boot is very prone to tearing and its recommended that a silicon replacement be installed. This was such an issue, that Audi revised the hose clamps to a smoothed inner edge version.

Bypass Valve/Diverter Valve Failure:
The originally equipped Bosch units have a rubber diaphragm design. They have been known to fail even under normal usage.

F-Hose Tearing:
The 2000 and early 2001 model S4's incorporated an "F" shaped hose with the intake system. These rubber hoses are prone to cracking or tearing. There are multiple aftermarket replacements available, silicon and metal.

Mass Air Flow (MAF) Sensor Failure:
The 2000 model S4 was shipped with problematic Bosch MAF units, these can easily be replaced with the Hitachi part from the 2001-2002 models.

Production Figures

Manual - 10,550 (72%)
Auto - 4,184 (28%)
Total - 14,734

Manual - 947 (62%)
Auto - 592 (38%)
Total - 1,539

Model Year Changes

Several revisions were made to the Audi S4 in 2001, so many, that people often call the revised versions 2001.5's.

  • Larger oil inlet lines for turbos
  • S4 badges were changed (front grill, steering wheel, gauges, trunk lid)
  • ESP (traction control) became standard equipment
  • Chrome mirror caps with Sport Package
  • Extended factory warrenty (4year/50000 Miles instead of 3year/50000 Miles)